Spanner bars and other secondary support structures are commonly used in commercial aircraft for wire bundle management. A typical spanner bar includes a thin gauge member having a repeating pattern of mounting holes separated by lands.
The spanner bars may be secured to primary aircraft structures. Wire support hardware such as p-clamps and ring posts are fastened to the spanner bars, and wire bundles are secured to the wire support hardware.
A ring post may be fastened to a spanner bar as follows. The ring post is positioned on a front side of the spanner bar. A threaded end of the ring post is aligned with a select open hole of the spanner bar. The threaded end of the ring post is maneuvered through the select hole until threads are exposed on a back side of the spanner bar. A loose washer and nut are placed over and threaded onto the threaded end of the ring post. The nut is tightened with a hand tool until firmly clamped against the spanner bar. This process is repeated for each ring post.
It would be desirable to reduce part count and installation time of attaching wire support hardware to a spanner bar. Even a seemingly trivial reduction for a single nut and washer can be significant due to the large number of fastening operations on secondary support structures in a commercial aircraft.